Thecus has made quite a name for itself when it comes to entry to mid-range NAS devices, its become something of a household name all over the world in this fairly new and growing market. A NAS or Network Attached Storage device is something that's very common in one way or another for businesses to use, although some might use a file server instead. However, the home and SOHO market has really taken to NAS appliances as an affordable backup and storage solution.

The N5200 Pro from Thecus is more for the small business market and it's a step up from Thecus' previous products, although it has a lot in common with the N5200. The chassis is identical and so are the basic features such as five 3.5-inch drive bays, a single eSATA connector, three USB ports and a type-B USB port for client mode usage. The N5200B Pro also has dual Gigabit Ethernet interfaces, and for those who think they'll use it, there is also an N5200BR Pro which comes with a built-in four port Gigabit Ethernet switch and a fifth Gigabit Ethernet interface.

The internals have been given a serious overhaul and we're looking at a 1.5GHz Celeron M processor with 1MB of L2 cache operating at a 400MHz bus, this has been paired up with 512MB of RAM. The original N5200 only features a 600MHz Celeron M and 256MB of memory. The downside to this is that the CPU is now actively cooled and we think that Thecus could've done this better by adding some kind of low profile heatpipe cooling, as the last thing you want is the CPU fan failing on your NAS. It also adds a bit of noise since the fan is quite small; although saying that, the rear 120mm fan and the PSU fan are likely to drown out any noise made by the CPU fan.

The motherboard used is actually a modified mini-ITX board which has been extended slightly to fit the LEDs that you see on the front of the N5200 Pro. It also has a different layout when it comes to the connectors over what you'd normally see on motherboards, as the board has been designed specifically for Thecus. There's a slot on the bottom of the board which looks something like a x16 PCI Express slot and this interfaces with the riser card onto which the drives connect. There's a second small riser card on the top of the board which will either accommodate the second Ethernet port or the four port switch.

The OS which is a Linux derivative is loaded on a 128MB IDE DoM (Disk on Module), although Thecus are using a notebook style IDE connector to reduce the space used on the motherboard. It's quite easy to access the internals of the N5200 Pro, all you have to do is release three thumb screws and the back slides out, although you have to be careful as the rear fan is connected to the motherboard. The overall construction feels very solid, although the plastic latches on the hard drive caddies felt a bit cheap considering the rest of the device. However, it's unlikely they'll snap and they're not something you'll be yanking at on a daily basis.

Each of the hard drive caddies also have a lock and the drives can as such be individually locked into the N5200 Pro. Mounting the drives could've been done better, although each drive is screwed in to the caddies from the bottom by four screws each, so it'll take a little while to install five drives. However, this is a higher-end device for its intended market and using some kind of caddy-less solution might not be in Thecus' best interests, since the N5200 Pro tries to compete with a wide range of storage appliances and looks also count in this business too.

The USB ports can be used for a variety of things such as printer server or additional storage, and they can even be used with some USB Wi-Fi adapters to turn the N5200 Pro into a Wi-Fi access point, although there's no mention of what USB dongles work and apparently you have to contact Thecus for a list of compatible devices. We're not quite sure why they can't simply put a list up on the website, as this would make it a lot easier for all parties.

To copy data from a USB drive onto the RAID, you attach the USB drive to one of the USB ports and manually use the controls on the front of the N5200 Pro to select the option which allows you to copy the data onto it. This is slightly awkward, but it should be faster for large amounts of data than doing it over the network, even considering the fact that the N5200 Pro features Gigabit Ethernet. It's quiet a simple process of pressing the down button and then the enter button, but it still means you have to walk over to the NAS which might be stuck in a cupboard or a server room somewhere depending on how you use it.

The type-B USB port is used for attaching the N5200 Pro directly to a PC, but why you would want to use this feature is beyond us as you don't get access to all the files on the RAID. Instead, you have to allocate a certain amount of space to what is referred to as the USB Target in the settings, which is quite confusing and there's no real explanation in the manual as to what the USB Target is. It might be handy to have a USB accessible volume on the RAID array, but this is a NAS, not a DAS (Direct Attached Storage) device. It almost seems as if Thecus has added this feature just because they can.

Let's move on and take a look at some of the software features that are on offer, and this is where the N5200 Pro stands out compared to the N5200.